Method and apparatus for forming threads or like filaments from aqueous dispersions of rubber or the like



July w, 1934. E. A MURPHY 1,966,040

METHOD AND APPARATUS FOR FORMING THREADS OR LIKE FILAMENTS 1 FROM AQUEOUS DISPERSIONS 0F RUBBER OR THE LIKE Filed .Feb. 17, 1933 11111111111 i l l Patented July 10, 1934 TES ATENT OFFIE THE LIKE Edward Arthur Murphy,

Wylde Green, Birmingham, England, assignor to Dunlop Rubber Company, Limited, a British corporation Application February 17, 1933, Serial No. 657,159 In Great Britain April 9, 1932 3 Claims.

This invention is concerned with improved means of preparing threads or filaments from dispersions of substances in liquid media which tend to sediment or cream, such as those in 5 which the dispersed materials have different densities from that of the dispersion medium.

Dispersions of this kind tend to sediment or settle in an upward or downward direction according to the differences in specific gravity of the continuous and dispersed phases.

The object of this invention is to reduce or entirely to obviate difficulties due to upward or downward sedimentation of the constituents.

In my invention rubber articles, particularly threads and filaments are made by supplying suitable aqueous dispersions to a vessel provided with orifices or jets and through which it passes into contact with a setting, coagulating or solidifying liquid and in supplying the dispersions continuously into the vessel in such a way that a constant head of aqueous dispersion is maintained within, the vessel and that circulation within the vessel is made continuous by supplying the dispersion, thereto in excess of that passed through the orifice, removing in a continuous manner the excess of dispersion from the upper surface of the vessel, and supplying additional di persion required for filling the vessel to the constant head preferablyat a level substantially adjacent the base thereof.

In one embodiment of the invention the plane surface containing the orifices from which the threads are formed is partly immersed in the solution which is used in the ensuing process and above and below the vessel containing the plane surface in which the jet orifices are situated are positioned two reservoirs, the upper one attached to the vessel by a suitable pipe and controlling means for regulating the flow into the threadforming vessel, and the lower reservoir being positioned to receive the overflow therefrom.

The container or jet box for forming the threads or filaments of rubber from the aqueous dispersions of the kinds hereinafter specified comprises or is in connection with an orifice the bore of which preferably does not exceed two millimetres in length, with an inner tube of such a length as to reach preferably to substantially the base of the container or jet box and which can be connected with the supply of aqueous dispersions aforesaid and with a drainage outlet,

preferably near the top.

The container or jet box is preferably inclined to the vertical and preferably its rear face is provided with the draining orifice preferably near the top so that the cream which tends to settle upwards, or other matter such as sediment which has risen to the top, may be continuously removed through the drainage orifice, which is also used to maintain the latex at a constant level or head.

The dispersions comprise those consisting of or containing rubber, gutta-percha, balata or similar resins occurring naturally or artificially obtained.

Such artificial aqueous dispersions may include those of coagulated rubber, vulcanized rubber, synthetic rubber, waste or reclaim. If desired any of the aforementioned dispersions may be used alone or in admixture with one another.

Any of the aforesaid dispersions may contain the usual known compounding ingredients and/or may be in concentrated form.

Concentrates such as are obtained in Patent No. 1,8 %,164, February 23, 1932, to which may be added any one or more of the usual compounding ingredients may also be used.

The invention may be used in conjunction with the process and apparatus claimed in the specification Patent No. 1,887,190 and with the device of co-pending application Ser. 582,769, filed December 23, 1931, but is not limited thereto.

In order that the said invention may be clearly understood and more readily carried into effect, the same will now be described more fully by way of example with reference to the accompanying diagrammatic drawing of a part sectional side elevation of apparatus for carrying out the invention.

The aqueous dispersion of rubber or the like material contained in a reservoir 1 is made to enter continuously a container or thread forming vessel 4 through a connection pipe 2 and a controlling means 3 for regulating the flow via an inner tube 9 held in position by a rubber washer l3 and a nut 14. Before entering the vessel 4 the aqueous dispersion is filtered by a fine muslin gauze 12 also held in position by the rubber washer l3 and the nut 14. The orifice or jets 6 of the container 4 are immersed in a bath 5 containing the setting, coagulating or solidifying liquid. 100 ,Some of the aqueous dispersions of rubber or the like material flows out through the orifice 6, the bore of which preferably does not exceed two millimetres in length, into the setting, coagulating or solidifying bath 5, when it immediately rises as 105 a solidified thread supported by the setting, coagulating or solidifying liquid.

The inner tube 9 is preferably of such a length as to reach a level 9 substantially adjacent the base of the container 4. In this way it is possible 110 to keep all the liquid within the container 4 in continuous motion.

Most of the liquid leaving 9 rises within the vessel 4 to a constant height 7 from where excess of dispersion is removed in a continuous manner from the rear face of the container at 8. Thus the aqueous dispersion of rubber or the like material is made to circulate continuously within the aforesaid vessel or container 4 maintaining a constant head of the aqueous dispersion at '7.

The excess of dispersion removed at 8 is conducted by a pipe 10 to a lower reservoir 11 positioned to receive the overflow.

The plane surface in which the jet orifices 6 are situated is preferably inclined to the vertical as shown.

Having now particularly described and ascertained my invention, what I claim is:

1. A method for the manufacture of rubber articles particularly threads and filaments of rubber or the like material from aqueous dispersions with comprises continuously supplying the dispersions to a vessel near the base thereof, passing dispersion from said vessel through an orifice into contact with a setting liquid and removing in a continuous manner excess of dispersion from its upper surface to maintain an upward circulation in said vessel.

2. A method for the manufacture of rubber articles particularly threads and filaments of rubber or the like material from aqueous dispersions which comprises maintaining a body of said dispersion under constant head, withdrawing thread-like streams from said body into a setting medium, supplying dispersion to said body of latex below the level at which said filamentary streams are withdrawn, overflowing and withdrawing excess dispersion at a level above that at which said filamentary streams are withdrawn to maintain a circulation within said body of dispersion.

3. A method of manufacturing rubber articles particularly threads and filaments of rubber or the like material from aqueous dispersions thereof which comprises maintaining a body of said dispersion, withdrawing a stream of dispersion from said body below and into a bath of a setting medium, supplying dispersion to said body below the level at which said streams are withdrawn into said setting medium and overflowing said dispersion at a level above that at which said streams are withdrawn to maintain a substantially constant head and a circulation in said body of dispersion.

EDWARD ARTHUR MURPHY. 

